Robust design of countercurrent adsorption separation: 3. Nonstoichiometric systems

Authors

  • Marco Mazzotti,

    1. Dipartimento di Chimica, Politecnico di Milano, 20131 Milano, Italy
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  • Giuseppe Storti,

    1. Dipartimento di Ingegneria Chimica e Materiali, Università degli Studi di Cagliari, 09123 Cagliari, Italy
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  • Massimo Morbidelli

    Corresponding author
    1. Laboratorium für Technische Chemie LTC, ETH Zentrum, Universitätstrasse 6, CH-8092 Zürich, Switzerland
    • Laboratorium für Technische Chemie LTC, ETH Zentrum, Universitätstrasse 6, CH-8092 Zürich, Switzerland
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Abstract

The separation of a multicomponent mixture in a countercurrent adsorptive separation unit is analyzed. A procedure for the optimal and robust design of the operating conditions of the unit is developed in the frame of equilibrium theory, where the adsorption equilibria are described through the constant selectivity nonstoichiometric Langmuir model, while mass-transfer resistances and axial dispersion are neglected. This allows for extending the results previously obtained for systems characterized by either the linear or stoichiometric Langmuir isotherm to cases where the adsorbates exhibit rather different loading capacities. Analogies and differences among these three equilibrium models with respect to the criteria for the choice of operating conditions of countercurrent separation units are discussed. A comparison between model predictions and experimental data assesses the reliability and accuracy of the theoretical results achieved in this work.

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